1. Field of the Invention
The present invention relates generally to push-button tuners for radio receivers and more particularly to a push-button tuner in which two preset broadcasting frequencies can be desiredly selectively tuned in by each push-button.
2. Description of Prior Art
Widely known is a push-button tuner comprising a plurality of push-buttons each of which is set to tune in to a preset broadcasting frequency so that a desired broadcasting frequency is tuned in by depressing a selected one of the push-buttons into its actuated position. In such a push-button tuner, usually, only one broadcasting station could be selected by one push-button so that in order to tune in to several broadcasting stations by push-buttons it has been necessary to provide several push-buttons corresponding to the number of broadcasting stations. To increase the number of push-buttons, however, it is necessary to enlarge, in the direction perpendicular to the axial direction of a tuning shaft, the length of an actuator plate which moves as the tuning shaft moves to thereby define the position of a variable tuning element. In the case where the length of the actuator plate is elongated, however, there is a tendency for the actuator plate incline in the direction of movement when a tuning shaft near each of opposite ends of a tuner is retracted. If the actuator plate inclines, there are disadvantages that not only the smooth movement of the actuator plate is made difficult but there is a possibility of causing an erroneous tuning operation. In a push-botton tuner which is intended to be reduced in size, it is necessary to reduce the depth of the actuator plate and there is a strong possibility that the actuator plates will incline.